At the resting membrane potential of an excitable cell, the driving force for ions is?

At a resting membrane potential of -90 mV, there is not only a large chemical driving force, but also a large electrical driving force acting upon external Na+ to cause it to diffuse into the cell.

Explanation:

the index of refraction of the second medium is higher. i just took the test trust me !

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added